Properties & Information

Hackmanite

Hackmanite

HackmaniteSCIENCE / MINERALOGYHackmanite is a sulfur-bearing variety of sodalite, a sodium aluminosilicate chloride mineral. It is famous for tenebrescence: some specimens reversibly deepen or change color after exposure to ultraviolet...

Hackmanite

HackmaniteSCIENCE / MINERALOGYHackmanite is a sulfur-bearing variety of sodalite, a sodium aluminosilicate chloride mineral. It is famous for tenebrescence: some specimens reversibly deepen or change color after exposure to ultraviolet...

Gyrolite

Gyrolite

GyroliteSCIENCE / MINERALOGYGyrolite is a hydrated calcium silicate mineral with a complex sheet structure and variable water content. It crystallizes in the triclinic system and commonly forms pearly white, colorless,...

Gyrolite

GyroliteSCIENCE / MINERALOGYGyrolite is a hydrated calcium silicate mineral with a complex sheet structure and variable water content. It crystallizes in the triclinic system and commonly forms pearly white, colorless,...

Guinea Fowl Quartz

Guinea Fowl Quartz

Guinea Fowl QuartzSCIENCE / MINERALOGYGuinea Fowl Quartz is a trade name for speckled quartz-rich material containing contrasting feldspar and dark mineral inclusions, commonly described commercially as tourmaline-bearing. The host is...

Guinea Fowl Quartz

Guinea Fowl QuartzSCIENCE / MINERALOGYGuinea Fowl Quartz is a trade name for speckled quartz-rich material containing contrasting feldspar and dark mineral inclusions, commonly described commercially as tourmaline-bearing. The host is...

Guinea Fowl Jasper

Guinea Fowl Jasper

Guinea Fowl JasperSCIENCE / MINERALOGYGuinea Fowl Jasper is a trade name for speckled South African lapidary material containing light and dark mineral grains reminiscent of guinea-fowl plumage. Commercial descriptions identify...

Guinea Fowl Jasper

Guinea Fowl JasperSCIENCE / MINERALOGYGuinea Fowl Jasper is a trade name for speckled South African lapidary material containing light and dark mineral grains reminiscent of guinea-fowl plumage. Commercial descriptions identify...

Grenatite

Grenatite

GrenatiteSCIENCE / MINERALOGYGrenatite is a modern trade name for a garnet-rich ornamental rock from Madagascar. Commercial material shows abundant tiny red garnet crystals distributed across a quartz-feldspar matrix. Because it...

Grenatite

GrenatiteSCIENCE / MINERALOGYGrenatite is a modern trade name for a garnet-rich ornamental rock from Madagascar. Commercial material shows abundant tiny red garnet crystals distributed across a quartz-feldspar matrix. Because it...

Greenland Jade

Greenland Jade

Greenland JadeSCIENCE / MINERALOGYGreenland Jade is a locality and trade name for jade material from Greenland. Jade is a gemological rock term that can refer to nephrite—a dense felted aggregate...

Greenland Jade

Greenland JadeSCIENCE / MINERALOGYGreenland Jade is a locality and trade name for jade material from Greenland. Jade is a gemological rock term that can refer to nephrite—a dense felted aggregate...